Projection-based user interface

1. A computing device with a virtual touch screen, comprising:

a projector configured to project a user interface image;

a depth camera configured to detect objects in a vicinity of the user interface image;

a memory including a touch service and a User Input (UI) device driver; and

an electronic processor,

wherein, when executing the touch service, the electronic processor is configured to:

receive image data from the depth camera,

perform a calibration process to generate a map that maps coordinates of the image data received by the depth camera to coordinates of the user interface image projected by the projector based on an image projected by the projector and captured by the depth camera, wherein the touch service performs the calibration process by inserting a watermark array into the user interface image, wherein to generate the map comprises to compare a position and shape of the watermark array projected by the projector with the position and shape of the watermark array captured by the depth camera, and

analyze the image data to generate touch event data,

wherein, when executing the UI device driver, the electronic processor is configured to:

receive the touch event data generated by the touch service, and

report the touch event data to an operating system of the computing device, and

wherein the touch service and UI device driver comprise system level software that is executable by the electronic processor prior to a user logging onto the computing device,

wherein, when the electronic processor executes the touch service, the electronic processor is further configured to update the map at a same rate as a frame rate of the projector, and

wherein, when the electronic processor executes the touch service, the electronic processor is further configured to:

scale down content of the user interface image, and

position the watermark array around the outside of the content.

2. The computing device of claim 1 , wherein the operating system is operable to accept the touch event data during a first time system setup, a login window, and lock screen.

3. The computing device of claim 1 , wherein the UI device driver is registered with the operating system during boot up of the computing device.

4. The computing device of claim 1 , wherein the UI device driver complies with the Universal Serial Bus-Human Interface Device (USB-HID) class specification.

5. The computing device of claim 1 , wherein the memory further includes a graphics driver, and

wherein, when the electronic processor executes the graphics driver, the electronic processor is configured to override rendering of the user interface image with a calibration pattern prior to the user being logged onto the computing device.

6. The computing device of claim 1 , wherein, when the electronic processor executes the touch service, the electronic processor is further configured to perform the calibration process by overriding the user interface image with a calibration pattern.

7. The computing device of claim 1 , wherein the watermark array overlaps content of the user interface image.

8. A method of operating a computing device with a virtual touch screen, comprising:

projecting a user interface image onto a surface;

receiving image data from a depth camera;

performing a calibration process to generate a map that maps coordinates of the image data received by the depth camera to coordinates of the projected user interface image based on an image projected by a projector and captured by the depth camera, wherein the calibration process comprises inserting a watermark array into the user interface image, wherein to generate the map comprises to compare a position and shape of the watermark array projected by the projector with the position and shape of the watermark array captured by the depth camera;

analyzing the image data to generate touch event data; and

sending the touch event data to a User Input (UI) device driver that reports the touch event data to an operating system of the computing device;

wherein the UI device driver is a system level device driver that is operable prior to a user logging onto the computing device,

wherein performing the calibration process comprises updating the map at for each frame of the user interface image, and

wherein inserting the watermark array comprises scaling down content of the user interface image and positioning the watermark array outside a perimeter of the content.

9. The method of claim 8 , comprising reporting the touch event data to the operating system during a first time system setup, a login window, and lock screen.

10. The method of claim 8 , comprising registering the UI device driver with the operating system during boot up of the computing device.

11. The method of claim 8 , wherein the UI device driver complies with the Universal Serial Bus-Human Interface Device (USB-HID) class specification.

12. The method of claim 8 , comprising overriding rendering of the user interface image with a calibration pattern prior to the user being logged onto the computing device.

13. The method of claim 8 , wherein performing the calibration process comprises overriding the user interface image with a calibration pattern.

14. The method of claim 8 , wherein inserting the watermark array comprises overlapping the watermark array with contents of the user interface image.

15. A tangible, non-transitory, computer-readable medium comprising instructions that, when executed by a processor, direct the processor to operate a computing device with a virtual touch screen, the instructions to direct the processor to:

project a user interface image onto a surface;

receive image data from a depth camera;

perform a calibration process to generate a map that maps coordinates of the image data received by the depth camera to coordinates of the projected user interface image based on an image projected by a projector and captured by the depth camera, wherein the calibration process comprises inserting a watermark array into the user interface image, wherein to generate the map comprises to compare a position and shape of the watermark array projected by the projector with the position and shape of the watermark array captured by the depth camera;

analyze the image data to generate touch event data; and

send the touch event data to a User Input (UI) device driver that reports the touch event data to an operating system of the computing device;

wherein the UI device driver is a system level device driver that is operable prior to a user logging onto the computing device,

wherein performing the calibration process comprises updating the map at for each frame of the user interface image, and

wherein inserting the watermark array comprises scaling down content of the user interface image and positioning the watermark array outside a perimeter of the content.

16. The computer-readable medium of claim 15 , wherein the instructions direct the processor to report the touch event data to the operating system during a first time system setup, a login window, and lock screen.

17. The computer-readable medium of claim 15 , wherein the instructions direct the processor to register the UI device driver with the operating system during boot up of the computing device.

18. The computer-readable medium of claim 15 , wherein the UI device driver complies with the Universal Serial Bus-Human Interface Device (USB-HID) class specification.

19. The computer-readable medium of claim 15 , wherein the instructions direct the processor to override rendering of the user interface image with a calibration pattern prior to the user being logged onto the computing device.